Speakers/Capacitors

[jonathand1000]

Hi,
I've noticed that in some (digital) loudspeaker drive circuits there is a capacitor placed before the loudspeaker. What is the purpose of this? Is it to make the square wave more sinusoidal?

Thanx alot,
Jon

 

[Exo]

Its mostly used to keep DC away from the speaker.
The capacitor will let AC (music) pass, but will form a barrier for DC

 

[Screech]

(digital) loudspeaker drive circuits ?

Caps can act as filters to filter unwanted frequencies.
You dont want low frequency to go to a tweeter, so, filter some of the low frequency out.

You want high frequencies going to a subwoofer, so filter some of the high frequencies out.

Use the chart below to sellect coil/capacitor for 6 db frequency reduction.

 

[jonathand1000]

Re:

Ah, thanks alot, I see now...that's cleared up something I've been in the dark on for a while. Just shows how much of a newbie I am I suppose!

Anyway thanks,
Jon